i have asked this question on numerous forums and haven't had much luck on anything close to "blue prints".
there is a thread a couple of pages back on this topic, and may give you some tips for starters.
i have desperately resorted to making my own now. i have pulled the front end out of my vit, and have the old brackets on the table. i just got some graph paper, measure it all up, and i've sort of made a 50mm/2" dropped left hand mount. i can only make the right hand one once i have made the left hand and fitted it up.
if you lower the diff too much, it will hit on the steering components, and the pinion flange may not have room to clear. the 3rd mounting may be a problem when lowering 2".
seeing as the whole diff is not dropped, and only the front is, you cant just make a straigh 2" drop bracket, as there will need to be some angles involved as the front tilts forward on the 3rd mounts radious. this means the left hand mount will need to have some angles in it to mount flush on the diff housing with the 4 bolts.
i will post up once i have made mine with most details and how i did it, and what didnt work and so on.
i am also making a new upper A frame for the rear diff, replacing the restrictive ball joint. this will be made from thick wall tubing and 3 trailing arm hi-flex bushes. i was originally going to use a rose joint on the diff mount like calmini, but i do a lot of water and mud driving, and it might not last the distance. the mount to the diff on the A arm will have a 360* pivot built in, meaning almost 0 resistance when flexing. only shocks, and brake lines will be the limiting factor.